1. Field of the Invention
The present invention relates to stereophonic speaker systems, and more particularly concerns an improved combination of speaker characteristics with speaker driving component signals to provide improved stereophonic sound.
2. Description of Related Art
In reproduction of stereophonic sound, electrical signals generally representing left and right channel stereo input sounds are combined or processed and fed to left and right channel speaker systems or to various combinations of speaker systems, with the goal of reproducing for the listener a sound that most realistically depicts sound heard during an actual, live performance. In attempts to achieve this goal, electrical stereophonic signals have been combined and processed in various manners. Major efforts have been made in careful design and manufacture of recording, mixing and production equipment so that the electrical end product will reflect as closely as possible precisely what performing artists, engineers, mixers or producers wish to convey to the listener. Signals have been fed to speakers positioned in various locations and in various groups, and speakers have been energized by various combinations of stereo signals in further attempts to improve realism of the sound. Artificial time delays, reverberation techniques and deliberate reflections from various walls have been employed, often at the expense of introduction of extraneous information of a type not originally present, thus actually changing the effect of the original performance. Yet, all the prior effort has not resulted in attainment of the goal of realistic reproduction of the sound of a live performance.
The spatial acoustical field produced in a live performance varies in accordance with acoustics of the performance area, and, importantly, in accordance with the type or nature of the performer or performers. For example, a solo vocalist or instrumentalist positioned at center stage will primarily provide sound known as direct field sound, that is radiated directly to the listeners in the audience. However, where performers are spread across a wide stage, for example, as in a performance of a large choral group or a large symphony orchestra, significant portions of sound received by the audience are reflected from various parts of the theater so that the audience receives a mixture of direct field sound, radiated directly from the performers, and sound known as reverberant field sound, that is reflected from the walls of the theater. In the case of some sounds, such as the immense organ chords of a Saint-Saens organ symphony, the music resounds and reverberates from surfaces in all areas of the theater.
Various combinations of speaker systems, including those that reflect a majority of sound from a wall behind the speaker, do not adequately reproduce all desired sounds with sufficient realism. Moreover, speaker systems arranged for one particular location or environment are not readily scaled up or down to operate in other environments so that, for example, a speaker system designed for a living room environment is not properly operable in an automobile, theater, or even outdoors.
Accordingly, it is an object of the present invention to provide a loudspeaker system that avoids or minimizes problems of prior systems and produces a spatial acoustical field which is more realistically representative of the live performance, and, moreover, is flexible in its application to different environments.